admin show url in list instead of id

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

this is an outcome of a user experience review we did on a project: the list views should be more semantic. the "id" means nothing to the end user. the URL path is what he cares about.

a more discrupting idea was to rename route to URL **in the interface** (i would not want to change the code, only the sonata translation files). i did it on a project by overwriting the relevant translation strings, and it looks indeed a lot better from an end user (=web editor) point of view. he should know what a URL is - but route means nothing to him. if there is no objections, i would like to push that into the bundle.